The transfer reaction CO+H.sub.2 O.fwdarw.CO.sub.2 +H.sub.2 of water gas is used for preparing hydrogen e.g. in the ammonia industry, and for increasing the hydrogen content of a synthetic gas, e.g. in the Fischer-Trosch synthesis. The reaction is most advantageous at a low temperature with respect to thermodynamic yield.
The catalysts used in the industry for the transfer reaction of water gas are either mixtures of iron and chrome oxides operating at a high temperature, or mixtures of copper, zinc and aluminum oxides at a lower temperature. Even the last-mentioned catalysts require a temperature of at least 200.degree. C., whereby the conversion of the reaction is partially limited by a reaction balance on the side of the reactants.
One of the most effective catalysts operating at the lowest temperatures of the water-gas transfer reaction is a compound prepared from a ruthenic carbonyl Ru.sub.3 (CO).sub.12 and a 2,2'-bipyridine and an inorganic oxide (U.S. Pat. No. 4,699,775). The preparation method of the catalyst is based on mixing the reactants in solid or liquid phase, in which case it is difficult to utilize the large specific area of the oxide component in the optimization of the catalyst activity.
Alcohols and aldehydes are generally prepared by means of hydroformylating processes. The catalysts used in industrial processes are generally homogeneous rhodium or cobalt carbonyls or phosphines. However, a heterogenous catalyst is usually easier to use, especially relative to the separation of the products. This advantage is especially emphasized when using expensive rhodium catalysts. The advantages of a heterogenous catalyst also include a higher thermal stability and minor corrosion problems.
A hydroformylating catalyst can also be prepared from ruthenic carbonyl and bipyridine, which catalyst together with an inorganic oxide forms a hetero catalyst system (U.S. patent application Ser. No. 424,289, now U.S. Pat. No. 5,001,685). The catalyst is prepared by admixing a ruthenic carbonyl, a bipyridine and an oxide in an organic solvent, from which the solvent is evaporated. The preparation method cannot effectively utilize the large surface area of the porous oxide component. As a result, the reproducibility of the catalyst preparation is disadvantageous, and the solubility into the product mixture is detrimental to heterogenous catalysis.